/*  $OpenBSD: ip_icmp.h,v 1.21 2005/07/31 03:30:55 pascoe Exp $ */
/*  $NetBSD: ip_icmp.h,v 1.10 1996/02/13 23:42:28 christos Exp $    */

/*
 * Copyright (c) 1982, 1986, 1993
 *  The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 *  @(#)ip_icmp.h   8.1 (Berkeley) 6/10/93
 */

#ifndef _NETINET_IP_ICMP_H_
#define _NETINET_IP_ICMP_H_

#include <netinet/ip.h>
#include <sys/cdefs.h>

__BEGIN_DECLS

/*
 * Interface Control Message Protocol Definitions.
 * Per RFC 792, September 1981.
 * RFC 950, August 1985. (Address Mask Request / Reply)
 * RFC 1256, September 1991. (Router Advertisement and Solicitation)
 * RFC 1108, November 1991. (Param Problem, Missing Req. Option)
 * RFC 1393, January 1993. (Traceroute)
 * RFC 1475, June 1993. (Datagram Conversion Error)
 * RFC 1812, June 1995. (adm prohib, host precedence, precedence cutoff)
 * RFC 2002, October 1996. (Mobility changes to Router Advertisement)
 */

/*
 * ICMP Router Advertisement data
 */
struct icmp_ra_addr {
    uint32_t  ira_addr;
    uint32_t  ira_preference;
};

/*
 * Structure of an icmp header.
 */
struct icmp {
    uint8_t  icmp_type;     /* type of message, see below */
    uint8_t  icmp_code;     /* type sub code */
    uint16_t icmp_cksum;        /* ones complement cksum of struct */
    union {
        uint8_t   ih_pptr;      /* ICMP_PARAMPROB */
        struct in_addr ih_gwaddr;   /* ICMP_REDIRECT */
        struct ih_idseq {
              uint16_t  icd_id;
              uint16_t  icd_seq;
        } ih_idseq;
        int32_t   ih_void;

        /* ICMP_UNREACH_NEEDFRAG -- Path MTU Discovery (RFC1191) */
        struct ih_pmtu {
              uint16_t  ipm_void;
              uint16_t  ipm_nextmtu;
        } ih_pmtu;

        struct ih_rtradv {
            uint8_t   irt_num_addrs;
            uint8_t   irt_wpa;
            uint16_t  irt_lifetime;
        } ih_rtradv;
    } icmp_hun;
#define icmp_pptr     icmp_hun.ih_pptr
#define icmp_gwaddr   icmp_hun.ih_gwaddr
#define icmp_id       icmp_hun.ih_idseq.icd_id
#define icmp_seq      icmp_hun.ih_idseq.icd_seq
#define icmp_void     icmp_hun.ih_void
#define icmp_pmvoid   icmp_hun.ih_pmtu.ipm_void
#define icmp_nextmtu      icmp_hun.ih_pmtu.ipm_nextmtu
#define icmp_num_addrs    icmp_hun.ih_rtradv.irt_num_addrs
#define icmp_wpa      icmp_hun.ih_rtradv.irt_wpa
#define icmp_lifetime     icmp_hun.ih_rtradv.irt_lifetime
    union {
        struct id_ts {
              uint32_t  its_otime;
              uint32_t  its_rtime;
              uint32_t  its_ttime;
        } id_ts;
        struct id_ip  {
              struct ip idi_ip;
              /* options and then 64 bits of data */
        } id_ip;
        uint32_t  id_mask;
        int8_t    id_data[1];
    } icmp_dun;
#define icmp_otime    icmp_dun.id_ts.its_otime
#define icmp_rtime    icmp_dun.id_ts.its_rtime
#define icmp_ttime    icmp_dun.id_ts.its_ttime
#define icmp_ip       icmp_dun.id_ip.idi_ip
#define icmp_mask     icmp_dun.id_mask
#define icmp_data     icmp_dun.id_data
};

/*
 * For IPv6 transition related ICMP errors.
 */
#define ICMP_V6ADVLENMIN    (8 + sizeof(struct ip) + 40)
#define ICMP_V6ADVLEN(p)    (8 + ((p)->icmp_ip.ip_hl << 2) + 40)

/*
 * Lower bounds on packet lengths for various types.
 * For the error advice packets must first insure that the
 * packet is large enough to contain the returned ip header.
 * Only then can we do the check to see if 64 bits of packet
 * data have been returned, since we need to check the returned
 * ip header length.
 */
#define ICMP_MINLEN 8               /* abs minimum */
#define ICMP_TSLEN  (8 + 3 * sizeof (n_time))   /* timestamp */
#define ICMP_MASKLEN    12              /* address mask */
#define ICMP_ADVLENMIN  (8 + sizeof (struct ip) + 8)    /* min */
#define ICMP_ADVLEN(p)  (8 + ((p)->icmp_ip.ip_hl << 2) + 8)
    /* N.B.: must separately check that ip_hl >= 5 */

/*
 * Definition of type and code field values.
 *  http://www.iana.org/assignments/icmp-parameters
 */
#define ICMP_ECHOREPLY      0       /* echo reply */
#define ICMP_UNREACH        3       /* dest unreachable, codes: */
#define ICMP_UNREACH_NET        0   /* bad net */
#define ICMP_UNREACH_HOST       1   /* bad host */
#define ICMP_UNREACH_PROTOCOL       2   /* bad protocol */
#define ICMP_UNREACH_PORT       3   /* bad port */
#define ICMP_UNREACH_NEEDFRAG       4   /* IP_DF caused drop */
#define ICMP_UNREACH_SRCFAIL        5   /* src route failed */
#define ICMP_UNREACH_NET_UNKNOWN    6   /* unknown net */
#define ICMP_UNREACH_HOST_UNKNOWN   7   /* unknown host */
#define ICMP_UNREACH_ISOLATED       8   /* src host isolated */
#define ICMP_UNREACH_NET_PROHIB     9   /* for crypto devs */
#define ICMP_UNREACH_HOST_PROHIB    10  /* ditto */
#define ICMP_UNREACH_TOSNET     11  /* bad tos for net */
#define ICMP_UNREACH_TOSHOST        12  /* bad tos for host */
#define ICMP_UNREACH_FILTER_PROHIB  13  /* prohibited access */
#define ICMP_UNREACH_HOST_PRECEDENCE    14  /* precedence violat'n*/
#define ICMP_UNREACH_PRECEDENCE_CUTOFF  15  /* precedence cutoff */
#define ICMP_SOURCEQUENCH   4       /* packet lost, slow down */
#define ICMP_REDIRECT       5       /* shorter route, codes: */
#define ICMP_REDIRECT_NET   0       /* for network */
#define ICMP_REDIRECT_HOST  1       /* for host */
#define ICMP_REDIRECT_TOSNET    2       /* for tos and net */
#define ICMP_REDIRECT_TOSHOST   3       /* for tos and host */
#define ICMP_ALTHOSTADDR    6       /* alternate host address */
#define ICMP_ECHO       8       /* echo service */
#define ICMP_ROUTERADVERT   9       /* router advertisement */
#define ICMP_ROUTERADVERT_NORMAL        0   /* normal advertisement */
#define ICMP_ROUTERADVERT_NOROUTE_COMMON    16  /* selective routing */
#define ICMP_ROUTERSOLICIT  10      /* router solicitation */
#define ICMP_TIMXCEED       11      /* time exceeded, code: */
#define ICMP_TIMXCEED_INTRANS   0       /* ttl==0 in transit */
#define ICMP_TIMXCEED_REASS 1       /* ttl==0 in reass */
#define ICMP_PARAMPROB      12      /* ip header bad */
#define ICMP_PARAMPROB_ERRATPTR 0       /* req. opt. absent */
#define ICMP_PARAMPROB_OPTABSENT 1      /* req. opt. absent */
#define ICMP_PARAMPROB_LENGTH   2       /* bad length */
#define ICMP_TSTAMP     13      /* timestamp request */
#define ICMP_TSTAMPREPLY    14      /* timestamp reply */
#define ICMP_IREQ       15      /* information request */
#define ICMP_IREQREPLY      16      /* information reply */
#define ICMP_MASKREQ        17      /* address mask request */
#define ICMP_MASKREPLY      18      /* address mask reply */
#define ICMP_TRACEROUTE     30      /* traceroute */
#define ICMP_DATACONVERR    31      /* data conversion error */
#define ICMP_MOBILE_REDIRECT    32      /* mobile host redirect */
#define ICMP_IPV6_WHEREAREYOU   33      /* IPv6 where-are-you */
#define ICMP_IPV6_IAMHERE   34      /* IPv6 i-am-here */
#define ICMP_MOBILE_REGREQUEST  35      /* mobile registration req */
#define ICMP_MOBILE_REGREPLY    36      /* mobile registration reply */
#define ICMP_SKIP       39      /* SKIP */
#define ICMP_PHOTURIS       40      /* Photuris */
#define ICMP_PHOTURIS_UNKNOWN_INDEX 1   /* unknown sec index */
#define ICMP_PHOTURIS_AUTH_FAILED   2   /* auth failed */
#define ICMP_PHOTURIS_DECRYPT_FAILED    3   /* decrypt failed */

#define ICMP_MAXTYPE        40

#define ICMP_INFOTYPE(type) \
    ((type) == ICMP_ECHOREPLY || (type) == ICMP_ECHO || \
    (type) == ICMP_ROUTERADVERT || (type) == ICMP_ROUTERSOLICIT || \
    (type) == ICMP_TSTAMP || (type) == ICMP_TSTAMPREPLY || \
    (type) == ICMP_IREQ || (type) == ICMP_IREQREPLY || \
    (type) == ICMP_MASKREQ || (type) == ICMP_MASKREPLY)

__END_DECLS

#endif /* _NETINET_IP_ICMP_H_ */
